/*    $NetBSD: getopt.c,v 1.16 1999/12/02 13:15:56 kleink Exp $    */

/*
 * Copyright (c) 1987, 1993, 1994
 *    The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    This product includes software developed by the University of
 *    California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if 0
static char sccsid[] = "@(#)getopt.c    8.3 (Berkeley) 4/27/95";
#endif

#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>

#ifndef __P
#define __P(x) x
#endif

#define _DIAGASSERT(x) assert(x)

#ifdef __weak_alias
__weak_alias(getopt,_getopt);
#endif

int    opterr = 1,        /* if error message should be printed */
    optind = 1,        /* index into parent argv vector */
    optopt,            /* character checked for validity */
    optreset;        /* reset getopt */
char    *optarg;        /* argument associated with option */

static char * _progname __P((char *));
int getopt_internal __P((int, char * const *, const char *));

static char *
_progname(nargv0)
    char * nargv0;
{
    char * tmp;

    _DIAGASSERT(nargv0 != NULL);

    tmp = strrchr(nargv0, '/');
    if (tmp)
        tmp++;
    else
        tmp = nargv0;
    return(tmp);
}

#define    BADCH    (int)'?'
#define    BADARG    (int)':'
#define    EMSG    ""

/*
 * getopt --
 *    Parse argc/argv argument vector.
 */
int
getopt(nargc, nargv, ostr)
    int nargc;
    char * const nargv[];
    const char *ostr;
{
    static char *__progname = 0;
    static char *place = EMSG;        /* option letter processing */
    char *oli;                /* option letter list index */
        __progname = __progname?__progname:_progname(*nargv);

    _DIAGASSERT(nargv != NULL);
    _DIAGASSERT(ostr != NULL);

    if (optreset || !*place) {        /* update scanning pointer */
        optreset = 0;
        if (optind >= nargc || *(place = nargv[optind]) != '-') {
            place = EMSG;
            return (-1);
        }
        if (place[1] && *++place == '-'    /* found "--" */
            && place[1] == '\0') {
            ++optind;
            place = EMSG;
            return (-1);
        }
    }                    /* option letter okay? */
    if ((optopt = (int)*place++) == (int)':' ||
        !(oli = strchr((char*)ostr, optopt))) {
        /*
         * if the user didn't specify '-' as an option,
         * assume it means -1.
         */
        if (optopt == (int)'-')
            return (-1);
        if (!*place)
            ++optind;
        if (opterr && *ostr != ':')
            (void)fprintf(stderr,
                "%s: illegal option -- %c\n", __progname, optopt);
        return (BADCH);
    }
    if (*++oli != ':') {            /* don't need argument */
        optarg = NULL;
        if (!*place)
            ++optind;
    }
    else {                    /* need an argument */
        if (*place)            /* no white space */
            optarg = place;
        else if (nargc <= ++optind) {    /* no arg */
            place = EMSG;
            if (*ostr == ':')
                return (BADARG);
            if (opterr)
                (void)fprintf(stderr,
                    "%s: option requires an argument -- %c\n",
                    __progname, optopt);
            return (BADCH);
        }
         else                /* white space */
            optarg = nargv[optind];
        place = EMSG;
        ++optind;
    }
    return (optopt);            /* dump back option letter */
}

